IDA GROVE, Iowa (AP) — A small town in northwestern Iowa has ended its decades-long practice of treating the city’s drinking water with fluoride. The Sioux City Journal reports that the Ida Grove City Council voted Monday to halt fluoride treatment in the city’s water supply. The move comes after city leaders and residents questioned whether fluoride in the water was effective at preventing tooth decay or presented health risks.

The city clerk’s office says a recent survey distributed through utility bills found that most respondents didn’t support fluoridation. Many cities use the mineral in drinking water to promote dental health, but the practice has been debated across the country. The city of roughly 2,000 residents began the practice in 1971.